Shoes made from sugar aim for smaller carbon footprint

An eco-friendly New Zealand startup hopes to transform the footwear industry and reduce waste by making shoes out of sugar.

"We've taken what has been a petroleum-based foam, which is one of the most broadly used components in all of the shoe industry, and we've replaced that with sugar," Joey Zwallinger, co-founder of Allbirds, said in an interview.

Instead, the company uses "Sweetfoam," the world's first "carbon negative polymer." That means the material takes more carbon out of the atmosphere than it produces.

Sugar cane sucks carbon dioxide out of the atmosphere and makes sugar. The leftover molasses is turned into ethanol, before undergoing a complex series of steps, which eventually form a polymer. The resulting material is molded into soles for shoes.

The company has  captured interest from some high-profile investors, including actor and environmentalist Leonardo DiCaprio. Now Allbirds plans to roll out the technology for all of its shoes, and Zwalling hopes other shoe makers will follow suit. 

"It's really the last piece that we hadn't solved, so if you look at our other shoes, every single other material has a bio-based story and this was really the one major piece that had the void," he said.